Languages

Programming language reference notes — syntax, idioms, and key patterns.

Go

Compiled, statically typed, concurrency-first language. Well-suited for backend services, CLIs, and data pipelines.

• go_basics — variables, types, fmt formatting
• go_functions — signatures, multiple returns, closures, defer, variadic
• go_control_flow — if/switch/for, range
• go_structs — struct definition, methods, embedding, memory layout
• go_interfaces — implicit implementation, type assertions, type switches
• go_pointers — pointer syntax, pass-by-reference, nil, pointer receivers
• go_collections — slices, maps, arrays
• go_errors — error interface, custom errors, iota
• go_concurrency — goroutines, channels, mutexes
• go_packages — package system, modules, go toolchain
• go_generics — type parameters, constraints

JavaScript

Single-threaded, event-driven, runs in browser and Node.js. Dynamically typed.

• js_core_language — types, variables, coercions, null/undefined
• js_functions — arrow functions, closures, scope, this
• js_objects_and_classes — objects, prototypes, classes, inheritance
• js_collections — arrays, maps, sets, loops
• js_async — event loop, promises, async/await
• js_modules — CommonJS, ESM, bundlers
• js_runtimes — Node.js, npm, Deno, Bun

TypeScript

JavaScript with static types. Structural type system; compiles to JS.

• ts_type_system — basic types, inference, any/unknown/never, type aliases
• ts_unions_and_intersections — union types, intersections, literal types
• ts_objects_and_interfaces — object types, interfaces, discriminated unions
• ts_classes — access modifiers, abstract classes, implements
• ts_generics — generic functions, constraints, type inference
• ts_type_narrowing — narrowing, type predicates, assertions
• ts_advanced_types — conditional types, mapped types, infer
• ts_utility_types — Partial, Required, Pick, Omit, Record, Readonly
• ts_enums_and_tuples — enums, const enums, tuples
• ts_local_dev — tsconfig, declaration files, Vite setup